From deaa51465105a7eda19a627b10372f4f7c51a4df Mon Sep 17 00:00:00 2001 From: Viresh Kumar Date: Wed, 11 Nov 2015 07:59:01 +0530 Subject: PM / OPP: Add debugfs support This patch adds debugfs support to OPP layer to export OPPs and their properties for all the devices. This creates a top level directory: /sys/kernel/debug/opp and then device specific directories (based on device names) inside it. For example: 'cpu0', 'cpu1', etc.. If multiple devices share the OPP table, then the real directory is created only for the first device. For all others, links are created to the real directory. Inside the device specific directory, a separate directory is created for each OPP. And within that files per opp property. Signed-off-by: Viresh Kumar Reviewed-by: Stephen Boyd Signed-off-by: Rafael J. Wysocki --- drivers/base/power/opp/Makefile | 1 + drivers/base/power/opp/core.c | 21 +++- drivers/base/power/opp/debugfs.c | 219 +++++++++++++++++++++++++++++++++++++++ drivers/base/power/opp/opp.h | 42 ++++++++ 4 files changed, 281 insertions(+), 2 deletions(-) create mode 100644 drivers/base/power/opp/debugfs.c (limited to 'drivers/base/power') diff --git a/drivers/base/power/opp/Makefile b/drivers/base/power/opp/Makefile index 33c1e18c41a4..19837ef04d8e 100644 --- a/drivers/base/power/opp/Makefile +++ b/drivers/base/power/opp/Makefile @@ -1,2 +1,3 @@ ccflags-$(CONFIG_DEBUG_DRIVER) := -DDEBUG obj-y += core.o cpu.o +obj-$(CONFIG_DEBUG_FS) += debugfs.o diff --git a/drivers/base/power/opp/core.c b/drivers/base/power/opp/core.c index b8e76f75073b..6aa172be6e8e 100644 --- a/drivers/base/power/opp/core.c +++ b/drivers/base/power/opp/core.c @@ -463,6 +463,7 @@ static void _kfree_list_dev_rcu(struct rcu_head *head) static void _remove_list_dev(struct device_list_opp *list_dev, struct device_opp *dev_opp) { + opp_debug_unregister(list_dev, dev_opp); list_del(&list_dev->node); call_srcu(&dev_opp->srcu_head.srcu, &list_dev->rcu_head, _kfree_list_dev_rcu); @@ -472,6 +473,7 @@ struct device_list_opp *_add_list_dev(const struct device *dev, struct device_opp *dev_opp) { struct device_list_opp *list_dev; + int ret; list_dev = kzalloc(sizeof(*list_dev), GFP_KERNEL); if (!list_dev) @@ -481,6 +483,12 @@ struct device_list_opp *_add_list_dev(const struct device *dev, list_dev->dev = dev; list_add_rcu(&list_dev->node, &dev_opp->dev_list); + /* Create debugfs entries for the dev_opp */ + ret = opp_debug_register(list_dev, dev_opp); + if (ret) + dev_err(dev, "%s: Failed to register opp debugfs (%d)\n", + __func__, ret); + return list_dev; } @@ -596,6 +604,7 @@ static void _opp_remove(struct device_opp *dev_opp, */ if (notify) srcu_notifier_call_chain(&dev_opp->srcu_head, OPP_EVENT_REMOVE, opp); + opp_debug_remove_one(opp); list_del_rcu(&opp->node); call_srcu(&dev_opp->srcu_head.srcu, &opp->rcu_head, _kfree_opp_rcu); @@ -673,6 +682,7 @@ static int _opp_add(struct device *dev, struct dev_pm_opp *new_opp, { struct dev_pm_opp *opp; struct list_head *head = &dev_opp->opp_list; + int ret; /* * Insert new OPP in order of increasing frequency and discard if @@ -703,6 +713,11 @@ static int _opp_add(struct device *dev, struct dev_pm_opp *new_opp, new_opp->dev_opp = dev_opp; list_add_rcu(&new_opp->node, head); + ret = opp_debug_create_one(new_opp, dev_opp); + if (ret) + dev_err(dev, "%s: Failed to register opp to debugfs (%d)\n", + __func__, ret); + return 0; } @@ -889,12 +904,14 @@ static int _opp_add_static_v2(struct device *dev, struct device_node *np) /* OPP to select on device suspend */ if (of_property_read_bool(np, "opp-suspend")) { - if (dev_opp->suspend_opp) + if (dev_opp->suspend_opp) { dev_warn(dev, "%s: Multiple suspend OPPs found (%lu %lu)\n", __func__, dev_opp->suspend_opp->rate, new_opp->rate); - else + } else { + new_opp->suspend = true; dev_opp->suspend_opp = new_opp; + } } if (new_opp->clock_latency_ns > dev_opp->clock_latency_ns_max) diff --git a/drivers/base/power/opp/debugfs.c b/drivers/base/power/opp/debugfs.c new file mode 100644 index 000000000000..ddfe4773e922 --- /dev/null +++ b/drivers/base/power/opp/debugfs.c @@ -0,0 +1,219 @@ +/* + * Generic OPP debugfs interface + * + * Copyright (C) 2015-2016 Viresh Kumar + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include +#include +#include +#include +#include + +#include "opp.h" + +static struct dentry *rootdir; + +static void opp_set_dev_name(const struct device *dev, char *name) +{ + if (dev->parent) + snprintf(name, NAME_MAX, "%s-%s", dev_name(dev->parent), + dev_name(dev)); + else + snprintf(name, NAME_MAX, "%s", dev_name(dev)); +} + +void opp_debug_remove_one(struct dev_pm_opp *opp) +{ + debugfs_remove_recursive(opp->dentry); +} + +int opp_debug_create_one(struct dev_pm_opp *opp, struct device_opp *dev_opp) +{ + struct dentry *pdentry = dev_opp->dentry; + struct dentry *d; + char name[25]; /* 20 chars for 64 bit value + 5 (opp:\0) */ + + /* Rate is unique to each OPP, use it to give opp-name */ + snprintf(name, sizeof(name), "opp:%lu", opp->rate); + + /* Create per-opp directory */ + d = debugfs_create_dir(name, pdentry); + if (!d) + return -ENOMEM; + + if (!debugfs_create_bool("available", S_IRUGO, d, &opp->available)) + return -ENOMEM; + + if (!debugfs_create_bool("dynamic", S_IRUGO, d, &opp->dynamic)) + return -ENOMEM; + + if (!debugfs_create_bool("turbo", S_IRUGO, d, &opp->turbo)) + return -ENOMEM; + + if (!debugfs_create_bool("suspend", S_IRUGO, d, &opp->suspend)) + return -ENOMEM; + + if (!debugfs_create_ulong("rate_hz", S_IRUGO, d, &opp->rate)) + return -ENOMEM; + + if (!debugfs_create_ulong("u_volt_target", S_IRUGO, d, &opp->u_volt)) + return -ENOMEM; + + if (!debugfs_create_ulong("u_volt_min", S_IRUGO, d, &opp->u_volt_min)) + return -ENOMEM; + + if (!debugfs_create_ulong("u_volt_max", S_IRUGO, d, &opp->u_volt_max)) + return -ENOMEM; + + if (!debugfs_create_ulong("u_amp", S_IRUGO, d, &opp->u_amp)) + return -ENOMEM; + + if (!debugfs_create_ulong("clock_latency_ns", S_IRUGO, d, + &opp->clock_latency_ns)) + return -ENOMEM; + + opp->dentry = d; + return 0; +} + +static int device_opp_debug_create_dir(struct device_list_opp *list_dev, + struct device_opp *dev_opp) +{ + const struct device *dev = list_dev->dev; + struct dentry *d; + + opp_set_dev_name(dev, dev_opp->dentry_name); + + /* Create device specific directory */ + d = debugfs_create_dir(dev_opp->dentry_name, rootdir); + if (!d) { + dev_err(dev, "%s: Failed to create debugfs dir\n", __func__); + return -ENOMEM; + } + + list_dev->dentry = d; + dev_opp->dentry = d; + + return 0; +} + +static int device_opp_debug_create_link(struct device_list_opp *list_dev, + struct device_opp *dev_opp) +{ + const struct device *dev = list_dev->dev; + char name[NAME_MAX]; + struct dentry *d; + + opp_set_dev_name(list_dev->dev, name); + + /* Create device specific directory link */ + d = debugfs_create_symlink(name, rootdir, dev_opp->dentry_name); + if (!d) { + dev_err(dev, "%s: Failed to create link\n", __func__); + return -ENOMEM; + } + + list_dev->dentry = d; + + return 0; +} + +/** + * opp_debug_register - add a device opp node to the debugfs 'opp' directory + * @list_dev: list-dev pointer for device + * @dev_opp: the device-opp being added + * + * Dynamically adds device specific directory in debugfs 'opp' directory. If the + * device-opp is shared with other devices, then links will be created for all + * devices except the first. + * + * Return: 0 on success, otherwise negative error. + */ +int opp_debug_register(struct device_list_opp *list_dev, + struct device_opp *dev_opp) +{ + if (!rootdir) { + pr_debug("%s: Uninitialized rootdir\n", __func__); + return -EINVAL; + } + + if (dev_opp->dentry) + return device_opp_debug_create_link(list_dev, dev_opp); + + return device_opp_debug_create_dir(list_dev, dev_opp); +} + +static void opp_migrate_dentry(struct device_list_opp *list_dev, + struct device_opp *dev_opp) +{ + struct device_list_opp *new_dev; + const struct device *dev; + struct dentry *dentry; + + /* Look for next list-dev */ + list_for_each_entry(new_dev, &dev_opp->dev_list, node) + if (new_dev != list_dev) + break; + + /* new_dev is guaranteed to be valid here */ + dev = new_dev->dev; + debugfs_remove_recursive(new_dev->dentry); + + opp_set_dev_name(dev, dev_opp->dentry_name); + + dentry = debugfs_rename(rootdir, list_dev->dentry, rootdir, + dev_opp->dentry_name); + if (!dentry) { + dev_err(dev, "%s: Failed to rename link from: %s to %s\n", + __func__, dev_name(list_dev->dev), dev_name(dev)); + return; + } + + new_dev->dentry = dentry; + dev_opp->dentry = dentry; +} + +/** + * opp_debug_unregister - remove a device opp node from debugfs opp directory + * @list_dev: list-dev pointer for device + * @dev_opp: the device-opp being removed + * + * Dynamically removes device specific directory from debugfs 'opp' directory. + */ +void opp_debug_unregister(struct device_list_opp *list_dev, + struct device_opp *dev_opp) +{ + if (list_dev->dentry == dev_opp->dentry) { + /* Move the real dentry object under another device */ + if (!list_is_singular(&dev_opp->dev_list)) { + opp_migrate_dentry(list_dev, dev_opp); + goto out; + } + dev_opp->dentry = NULL; + } + + debugfs_remove_recursive(list_dev->dentry); + +out: + list_dev->dentry = NULL; +} + +static int __init opp_debug_init(void) +{ + /* Create /sys/kernel/debug/opp directory */ + rootdir = debugfs_create_dir("opp", NULL); + if (!rootdir) { + pr_err("%s: Failed to create root directory\n", __func__); + return -ENOMEM; + } + + return 0; +} +core_initcall(opp_debug_init); diff --git a/drivers/base/power/opp/opp.h b/drivers/base/power/opp/opp.h index 7366b2aa8997..a6bd8d2c2b47 100644 --- a/drivers/base/power/opp/opp.h +++ b/drivers/base/power/opp/opp.h @@ -17,6 +17,7 @@ #include #include #include +#include #include #include #include @@ -53,6 +54,7 @@ extern struct mutex dev_opp_list_lock; * @dynamic: not-created from static DT entries. * @available: true/false - marks if this OPP as available or not * @turbo: true if turbo (boost) OPP + * @suspend: true if suspend OPP * @rate: Frequency in hertz * @u_volt: Target voltage in microvolts corresponding to this OPP * @u_volt_min: Minimum voltage in microvolts corresponding to this OPP @@ -63,6 +65,7 @@ extern struct mutex dev_opp_list_lock; * @dev_opp: points back to the device_opp struct this opp belongs to * @rcu_head: RCU callback head used for deferred freeing * @np: OPP's device node. + * @dentry: debugfs dentry pointer (per opp) * * This structure stores the OPP information for a given device. */ @@ -72,6 +75,7 @@ struct dev_pm_opp { bool available; bool dynamic; bool turbo; + bool suspend; unsigned long rate; unsigned long u_volt; @@ -84,6 +88,10 @@ struct dev_pm_opp { struct rcu_head rcu_head; struct device_node *np; + +#ifdef CONFIG_DEBUG_FS + struct dentry *dentry; +#endif }; /** @@ -91,6 +99,7 @@ struct dev_pm_opp { * @node: list node * @dev: device to which the struct object belongs * @rcu_head: RCU callback head used for deferred freeing + * @dentry: debugfs dentry pointer (per device) * * This is an internal data structure maintaining the list of devices that are * managed by 'struct device_opp'. @@ -99,6 +108,10 @@ struct device_list_opp { struct list_head node; const struct device *dev; struct rcu_head rcu_head; + +#ifdef CONFIG_DEBUG_FS + struct dentry *dentry; +#endif }; /** @@ -114,6 +127,8 @@ struct device_list_opp { * @opp_list: list of opps * @np: struct device_node pointer for opp's DT node. * @shared_opp: OPP is shared between multiple devices. + * @dentry: debugfs dentry pointer of the real device directory (not links). + * @dentry_name: Name of the real dentry. * * This is an internal data structure maintaining the link to opps attached to * a device. This structure is not meant to be shared to users as it is @@ -135,6 +150,11 @@ struct device_opp { unsigned long clock_latency_ns_max; bool shared_opp; struct dev_pm_opp *suspend_opp; + +#ifdef CONFIG_DEBUG_FS + struct dentry *dentry; + char dentry_name[NAME_MAX]; +#endif }; /* Routines internal to opp core */ @@ -143,4 +163,26 @@ struct device_list_opp *_add_list_dev(const struct device *dev, struct device_opp *dev_opp); struct device_node *_of_get_opp_desc_node(struct device *dev); +#ifdef CONFIG_DEBUG_FS +void opp_debug_remove_one(struct dev_pm_opp *opp); +int opp_debug_create_one(struct dev_pm_opp *opp, struct device_opp *dev_opp); +int opp_debug_register(struct device_list_opp *list_dev, + struct device_opp *dev_opp); +void opp_debug_unregister(struct device_list_opp *list_dev, + struct device_opp *dev_opp); +#else +static inline void opp_debug_remove_one(struct dev_pm_opp *opp) {} + +static inline int opp_debug_create_one(struct dev_pm_opp *opp, + struct device_opp *dev_opp) +{ return 0; } +static inline int opp_debug_register(struct device_list_opp *list_dev, + struct device_opp *dev_opp) +{ return 0; } + +static inline void opp_debug_unregister(struct device_list_opp *list_dev, + struct device_opp *dev_opp) +{ } +#endif /* DEBUG_FS */ + #endif /* __DRIVER_OPP_H__ */ -- cgit v1.2.3 From dc4e7b1fa20a840d2317fcfdaa1064fc09d2afcb Mon Sep 17 00:00:00 2001 From: Viresh Kumar Date: Thu, 19 Nov 2015 09:13:56 +0530 Subject: PM / OPP: Add missing doc comments Few doc-style comments were missing, add them. Rearrange another one to match the sequence within the structure. Signed-off-by: Viresh Kumar Acked-by: Pavel Machek Reviewed-by: Stephen Boyd Signed-off-by: Rafael J. Wysocki --- drivers/base/power/opp/opp.h | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'drivers/base/power') diff --git a/drivers/base/power/opp/opp.h b/drivers/base/power/opp/opp.h index a6bd8d2c2b47..b8880c7f8be1 100644 --- a/drivers/base/power/opp/opp.h +++ b/drivers/base/power/opp/opp.h @@ -51,8 +51,8 @@ extern struct mutex dev_opp_list_lock; * are protected by the dev_opp_list_lock for integrity. * IMPORTANT: the opp nodes should be maintained in increasing * order. - * @dynamic: not-created from static DT entries. * @available: true/false - marks if this OPP as available or not + * @dynamic: not-created from static DT entries. * @turbo: true if turbo (boost) OPP * @suspend: true if suspend OPP * @rate: Frequency in hertz @@ -126,7 +126,9 @@ struct device_list_opp { * @dev_list: list of devices that share these OPPs * @opp_list: list of opps * @np: struct device_node pointer for opp's DT node. + * @clock_latency_ns_max: Max clock latency in nanoseconds. * @shared_opp: OPP is shared between multiple devices. + * @suspend_opp: Pointer to OPP to be used during device suspend. * @dentry: debugfs dentry pointer of the real device directory (not links). * @dentry_name: Name of the real dentry. * -- cgit v1.2.3 From 013c074f8642d8e815ad670601f8e27155a74b57 Mon Sep 17 00:00:00 2001 From: "Strashko, Grygorii" Date: Tue, 10 Nov 2015 11:42:34 +0200 Subject: PM / sleep: prohibit devices probing during suspend/hibernation It is unsafe [1] if probing of devices will happen during suspend or hibernation and system behavior will be unpredictable in this case. So, let's prohibit device's probing in dpm_prepare() and defer their probing instead. The normal behavior will be restored in dpm_complete(). This patch introduces new DD core APIs: device_block_probing() It will disable probing of devices and defer their probes instead. device_unblock_probing() It will restore normal behavior and trigger re-probing of deferred devices. [1] https://lkml.org/lkml/2015/9/11/554 Signed-off-by: Grygorii Strashko Acked-by: Pavel Machek Signed-off-by: Rafael J. Wysocki --- drivers/base/base.h | 2 ++ drivers/base/dd.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++- drivers/base/power/main.c | 17 +++++++++++++++++ 3 files changed, 66 insertions(+), 1 deletion(-) (limited to 'drivers/base/power') diff --git a/drivers/base/base.h b/drivers/base/base.h index 1782f3aa386e..e05db388bd1c 100644 --- a/drivers/base/base.h +++ b/drivers/base/base.h @@ -131,6 +131,8 @@ extern void device_remove_groups(struct device *dev, extern char *make_class_name(const char *name, struct kobject *kobj); extern int devres_release_all(struct device *dev); +extern void device_block_probing(void); +extern void device_unblock_probing(void); /* /sys/devices directory */ extern struct kset *devices_kset; diff --git a/drivers/base/dd.c b/drivers/base/dd.c index a641cf3ccad6..b605f734b882 100644 --- a/drivers/base/dd.c +++ b/drivers/base/dd.c @@ -54,6 +54,13 @@ static LIST_HEAD(deferred_probe_active_list); static struct workqueue_struct *deferred_wq; static atomic_t deferred_trigger_count = ATOMIC_INIT(0); +/* + * In some cases, like suspend to RAM or hibernation, It might be reasonable + * to prohibit probing of devices as it could be unsafe. + * Once defer_all_probes is true all drivers probes will be forcibly deferred. + */ +static bool defer_all_probes; + /* * deferred_probe_work_func() - Retry probing devices in the active list. */ @@ -171,6 +178,30 @@ static void driver_deferred_probe_trigger(void) queue_work(deferred_wq, &deferred_probe_work); } +/** + * device_block_probing() - Block/defere device's probes + * + * It will disable probing of devices and defer their probes instead. + */ +void device_block_probing(void) +{ + defer_all_probes = true; + /* sync with probes to avoid races. */ + wait_for_device_probe(); +} + +/** + * device_unblock_probing() - Unblock/enable device's probes + * + * It will restore normal behavior and trigger re-probing of deferred + * devices. + */ +void device_unblock_probing(void) +{ + defer_all_probes = false; + driver_deferred_probe_trigger(); +} + /** * deferred_probe_initcall() - Enable probing of deferred devices * @@ -277,9 +308,20 @@ static DECLARE_WAIT_QUEUE_HEAD(probe_waitqueue); static int really_probe(struct device *dev, struct device_driver *drv) { - int ret = 0; + int ret = -EPROBE_DEFER; int local_trigger_count = atomic_read(&deferred_trigger_count); + if (defer_all_probes) { + /* + * Value of defer_all_probes can be set only by + * device_defer_all_probes_enable() which, in turn, will call + * wait_for_device_probe() right after that to avoid any races. + */ + dev_dbg(dev, "Driver %s force probe deferral\n", drv->name); + driver_deferred_probe_add(dev); + return ret; + } + atomic_inc(&probe_count); pr_debug("bus: '%s': %s: probing driver %s with device %s\n", drv->bus->name, __func__, drv->name, dev_name(dev)); @@ -393,6 +435,10 @@ int driver_probe_done(void) */ void wait_for_device_probe(void) { + /* wait for the deferred probe workqueue to finish */ + if (driver_deferred_probe_enable) + flush_workqueue(deferred_wq); + /* wait for the known devices to complete their probing */ wait_event(probe_waitqueue, atomic_read(&probe_count) == 0); async_synchronize_full(); diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c index 1710c26ba097..9d626ac08d9c 100644 --- a/drivers/base/power/main.c +++ b/drivers/base/power/main.c @@ -963,6 +963,9 @@ void dpm_complete(pm_message_t state) } list_splice(&list, &dpm_list); mutex_unlock(&dpm_list_mtx); + + /* Allow device probing and trigger re-probing of deferred devices */ + device_unblock_probing(); trace_suspend_resume(TPS("dpm_complete"), state.event, false); } @@ -1624,6 +1627,20 @@ int dpm_prepare(pm_message_t state) trace_suspend_resume(TPS("dpm_prepare"), state.event, true); might_sleep(); + /* + * Give a chance for the known devices to complete their probes, before + * disable probing of devices. This sync point is important at least + * at boot time + hibernation restore. + */ + wait_for_device_probe(); + /* + * It is unsafe if probing of devices will happen during suspend or + * hibernation and system behavior will be unpredictable in this case. + * So, let's prohibit device's probing here and defer their probes + * instead. The normal behavior will be restored in dpm_complete(). + */ + device_block_probing(); + mutex_lock(&dpm_list_mtx); while (!list_empty(&dpm_list)) { struct device *dev = to_device(dpm_list.next); -- cgit v1.2.3 From 5de85b9d57aba3ed2e04759e6db3b9e826dd0b06 Mon Sep 17 00:00:00 2001 From: Ulf Hansson Date: Wed, 18 Nov 2015 11:48:39 +0100 Subject: PM / runtime: Re-init runtime PM states at probe error and driver unbind There are two common expectations among several subsystems/drivers that deploys runtime PM support, but which isn't met by the driver core. Expectation 1) At ->probe() the subsystem/driver expects the runtime PM status of the device to be RPM_SUSPENDED, which is the initial status being assigned at device registration. This expectation is especially common among some of those subsystems/ drivers that manages devices with an attached PM domain, as those requires the ->runtime_resume() callback at the PM domain level to be invoked during ->probe(). Moreover these subsystems/drivers entirely relies on runtime PM resources being managed at the PM domain level, thus don't implement their own set of runtime PM callbacks. These are two scenarios that suffers from this unmet expectation. i) A failed ->probe() sequence requests probe deferral: ->probe() ... pm_runtime_enable() pm_runtime_get_sync() ... err: pm_runtime_put() pm_runtime_disable() ... As there are no guarantees that such sequence turns the runtime PM status of the device into RPM_SUSPENDED, the re-trying ->probe() may start with the status in RPM_ACTIVE. In such case the runtime PM core won't invoke the ->runtime_resume() callback because of a pm_runtime_get_sync(), as it considers the device to be already runtime resumed. ii) A driver re-bind sequence: At driver unbind, the subsystem/driver's >remove() callback invokes a sequence of runtime PM APIs, to undo actions during ->probe() and to put the device into low power state. ->remove() ... pm_runtime_put() pm_runtime_disable() ... Similar as in the failing ->probe() case, this sequence don't guarantee the runtime PM status of the device to turn into RPM_SUSPENDED. Trying to re-bind the driver thus causes the same issue as when re-trying ->probe(), in the probe deferral scenario. Expectation 2) Drivers that invokes the pm_runtime_irq_safe() API during ->probe(), triggers the runtime PM core to increase the usage count for the device's parent and permanently make it runtime resumed. The usage count is only dropped at device removal, which also allows it to be runtime suspended again. A re-trying ->probe() repeats the call to pm_runtime_irq_safe() and thus once more triggers the usage count of the device's parent to be increased. This leads to not only an imbalance issue of the usage count of the device's parent, but also to keep it runtime resumed permanently even if ->probe() fails. To address these issues, let's change the policy of the driver core to meet these expectations. More precisely, at ->probe() failures and driver unbind, restore the initial states of runtime PM. Although to still allow subsystem's to control PM for devices that doesn't ->probe() successfully, don't restore the initial states unless runtime PM is disabled. Signed-off-by: Ulf Hansson Reviewed-by: Kevin Hilman Signed-off-by: Rafael J. Wysocki --- drivers/base/dd.c | 2 ++ drivers/base/power/power.h | 2 ++ drivers/base/power/runtime.c | 26 ++++++++++++++++++++------ 3 files changed, 24 insertions(+), 6 deletions(-) (limited to 'drivers/base/power') diff --git a/drivers/base/dd.c b/drivers/base/dd.c index a641cf3ccad6..cd2d79b1bf01 100644 --- a/drivers/base/dd.c +++ b/drivers/base/dd.c @@ -340,6 +340,7 @@ probe_failed: dev_set_drvdata(dev, NULL); if (dev->pm_domain && dev->pm_domain->dismiss) dev->pm_domain->dismiss(dev); + pm_runtime_reinit(dev); switch (ret) { case -EPROBE_DEFER: @@ -695,6 +696,7 @@ static void __device_release_driver(struct device *dev) dev_set_drvdata(dev, NULL); if (dev->pm_domain && dev->pm_domain->dismiss) dev->pm_domain->dismiss(dev); + pm_runtime_reinit(dev); klist_remove(&dev->p->knode_driver); if (dev->bus) diff --git a/drivers/base/power/power.h b/drivers/base/power/power.h index 998fa6b23084..8b06193d4a5e 100644 --- a/drivers/base/power/power.h +++ b/drivers/base/power/power.h @@ -18,6 +18,7 @@ static inline void pm_runtime_early_init(struct device *dev) } extern void pm_runtime_init(struct device *dev); +extern void pm_runtime_reinit(struct device *dev); extern void pm_runtime_remove(struct device *dev); struct wake_irq { @@ -84,6 +85,7 @@ static inline void pm_runtime_early_init(struct device *dev) } static inline void pm_runtime_init(struct device *dev) {} +static inline void pm_runtime_reinit(struct device *dev) {} static inline void pm_runtime_remove(struct device *dev) {} static inline int dpm_sysfs_add(struct device *dev) { return 0; } diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c index e1a10a03df8e..ab3fcd9f6c98 100644 --- a/drivers/base/power/runtime.c +++ b/drivers/base/power/runtime.c @@ -1389,6 +1389,25 @@ void pm_runtime_init(struct device *dev) init_waitqueue_head(&dev->power.wait_queue); } +/** + * pm_runtime_reinit - Re-initialize runtime PM fields in given device object. + * @dev: Device object to re-initialize. + */ +void pm_runtime_reinit(struct device *dev) +{ + if (!pm_runtime_enabled(dev)) { + if (dev->power.runtime_status == RPM_ACTIVE) + pm_runtime_set_suspended(dev); + if (dev->power.irq_safe) { + spin_lock_irq(&dev->power.lock); + dev->power.irq_safe = 0; + spin_unlock_irq(&dev->power.lock); + if (dev->parent) + pm_runtime_put(dev->parent); + } + } +} + /** * pm_runtime_remove - Prepare for removing a device from device hierarchy. * @dev: Device object being removed from device hierarchy. @@ -1396,12 +1415,7 @@ void pm_runtime_init(struct device *dev) void pm_runtime_remove(struct device *dev) { __pm_runtime_disable(dev, false); - - /* Change the status back to 'suspended' to match the initial status. */ - if (dev->power.runtime_status == RPM_ACTIVE) - pm_runtime_set_suspended(dev); - if (dev->power.irq_safe && dev->parent) - pm_runtime_put(dev->parent); + pm_runtime_reinit(dev); } /** -- cgit v1.2.3 From 24c96dc79c5e76d3cff7a33f955a4d3244644766 Mon Sep 17 00:00:00 2001 From: Maruthi Bayyavarapu Date: Wed, 18 Nov 2015 01:12:00 +0530 Subject: PM / Domains: export symbols to add/remove devices from genpd Drivers which can be built as loadable module needs symbols - pm_genpd_add_device/pm_genpd_remove_device to add/remove devices to/from genpd. Those drivers create platform devices, which comes under a powerdomain. Signed-off-by: Maruthi Bayyavarapu Acked-by: Pavel Machek Signed-off-by: Rafael J. Wysocki --- drivers/base/power/domain.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'drivers/base/power') diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c index 167418e73445..e0dc12efd3cc 100644 --- a/drivers/base/power/domain.c +++ b/drivers/base/power/domain.c @@ -1252,6 +1252,7 @@ int __pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev, return ret; } +EXPORT_SYMBOL_GPL(__pm_genpd_add_device); /** * pm_genpd_remove_device - Remove a device from an I/O PM domain. @@ -1302,6 +1303,7 @@ int pm_genpd_remove_device(struct generic_pm_domain *genpd, return ret; } +EXPORT_SYMBOL_GPL(pm_genpd_remove_device); /** * pm_genpd_add_subdomain - Add a subdomain to an I/O PM domain. -- cgit v1.2.3 From 7de36b0aa51a5a59e28fb2da768fa3ab07de0674 Mon Sep 17 00:00:00 2001 From: Viresh Kumar Date: Wed, 9 Dec 2015 08:01:46 +0530 Subject: PM / OPP: Parse 'opp-supported-hw' binding OPP bindings allow a platform to enable OPPs based on the version of the hardware they are used for. Add support to the OPP-core to parse these bindings, by introducing dev_pm_opp_{set|put}_supported_hw() APIs. Signed-off-by: Viresh Kumar Tested-by: Lee Jones Signed-off-by: Rafael J. Wysocki --- drivers/base/power/opp/core.c | 148 ++++++++++++++++++++++++++++++++++++++++++ drivers/base/power/opp/opp.h | 5 ++ include/linux/pm_opp.h | 13 ++++ 3 files changed, 166 insertions(+) (limited to 'drivers/base/power') diff --git a/drivers/base/power/opp/core.c b/drivers/base/power/opp/core.c index 6aa172be6e8e..55cf1a99b532 100644 --- a/drivers/base/power/opp/core.c +++ b/drivers/base/power/opp/core.c @@ -559,6 +559,9 @@ static void _remove_device_opp(struct device_opp *dev_opp) if (!list_empty(&dev_opp->opp_list)) return; + if (dev_opp->supported_hw) + return; + list_dev = list_first_entry(&dev_opp->dev_list, struct device_list_opp, node); @@ -833,6 +836,145 @@ static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev) return 0; } +/** + * dev_pm_opp_set_supported_hw() - Set supported platforms + * @dev: Device for which supported-hw has to be set. + * @versions: Array of hierarchy of versions to match. + * @count: Number of elements in the array. + * + * This is required only for the V2 bindings, and it enables a platform to + * specify the hierarchy of versions it supports. OPP layer will then enable + * OPPs, which are available for those versions, based on its 'opp-supported-hw' + * property. + * + * Locking: The internal device_opp and opp structures are RCU protected. + * Hence this function internally uses RCU updater strategy with mutex locks + * to keep the integrity of the internal data structures. Callers should ensure + * that this function is *NOT* called under RCU protection or in contexts where + * mutex cannot be locked. + */ +int dev_pm_opp_set_supported_hw(struct device *dev, const u32 *versions, + unsigned int count) +{ + struct device_opp *dev_opp; + int ret = 0; + + /* Hold our list modification lock here */ + mutex_lock(&dev_opp_list_lock); + + dev_opp = _add_device_opp(dev); + if (!dev_opp) { + ret = -ENOMEM; + goto unlock; + } + + /* Make sure there are no concurrent readers while updating dev_opp */ + WARN_ON(!list_empty(&dev_opp->opp_list)); + + /* Do we already have a version hierarchy associated with dev_opp? */ + if (dev_opp->supported_hw) { + dev_err(dev, "%s: Already have supported hardware list\n", + __func__); + ret = -EBUSY; + goto err; + } + + dev_opp->supported_hw = kmemdup(versions, count * sizeof(*versions), + GFP_KERNEL); + if (!dev_opp->supported_hw) { + ret = -ENOMEM; + goto err; + } + + dev_opp->supported_hw_count = count; + mutex_unlock(&dev_opp_list_lock); + return 0; + +err: + _remove_device_opp(dev_opp); +unlock: + mutex_unlock(&dev_opp_list_lock); + + return ret; +} +EXPORT_SYMBOL_GPL(dev_pm_opp_set_supported_hw); + +/** + * dev_pm_opp_put_supported_hw() - Releases resources blocked for supported hw + * @dev: Device for which supported-hw has to be set. + * + * This is required only for the V2 bindings, and is called for a matching + * dev_pm_opp_set_supported_hw(). Until this is called, the device_opp structure + * will not be freed. + * + * Locking: The internal device_opp and opp structures are RCU protected. + * Hence this function internally uses RCU updater strategy with mutex locks + * to keep the integrity of the internal data structures. Callers should ensure + * that this function is *NOT* called under RCU protection or in contexts where + * mutex cannot be locked. + */ +void dev_pm_opp_put_supported_hw(struct device *dev) +{ + struct device_opp *dev_opp; + + /* Hold our list modification lock here */ + mutex_lock(&dev_opp_list_lock); + + /* Check for existing list for 'dev' first */ + dev_opp = _find_device_opp(dev); + if (IS_ERR(dev_opp)) { + dev_err(dev, "Failed to find dev_opp: %ld\n", PTR_ERR(dev_opp)); + goto unlock; + } + + /* Make sure there are no concurrent readers while updating dev_opp */ + WARN_ON(!list_empty(&dev_opp->opp_list)); + + if (!dev_opp->supported_hw) { + dev_err(dev, "%s: Doesn't have supported hardware list\n", + __func__); + goto unlock; + } + + kfree(dev_opp->supported_hw); + dev_opp->supported_hw = NULL; + dev_opp->supported_hw_count = 0; + + /* Try freeing device_opp if this was the last blocking resource */ + _remove_device_opp(dev_opp); + +unlock: + mutex_unlock(&dev_opp_list_lock); +} +EXPORT_SYMBOL_GPL(dev_pm_opp_put_supported_hw); + +static bool _opp_is_supported(struct device *dev, struct device_opp *dev_opp, + struct device_node *np) +{ + unsigned int count = dev_opp->supported_hw_count; + u32 version; + int ret; + + if (!dev_opp->supported_hw) + return true; + + while (count--) { + ret = of_property_read_u32_index(np, "opp-supported-hw", count, + &version); + if (ret) { + dev_warn(dev, "%s: failed to read opp-supported-hw property at index %d: %d\n", + __func__, count, ret); + return false; + } + + /* Both of these are bitwise masks of the versions */ + if (!(version & dev_opp->supported_hw[count])) + return false; + } + + return true; +} + /** * _opp_add_static_v2() - Allocate static OPPs (As per 'v2' DT bindings) * @dev: device for which we do this operation @@ -879,6 +1021,12 @@ static int _opp_add_static_v2(struct device *dev, struct device_node *np) goto free_opp; } + /* Check if the OPP supports hardware's hierarchy of versions or not */ + if (!_opp_is_supported(dev, dev_opp, np)) { + dev_dbg(dev, "OPP not supported by hardware: %llu\n", rate); + goto free_opp; + } + /* * Rate is defined as an unsigned long in clk API, and so casting * explicitly to its type. Must be fixed once rate is 64 bit diff --git a/drivers/base/power/opp/opp.h b/drivers/base/power/opp/opp.h index b8880c7f8be1..70f4564a6ab9 100644 --- a/drivers/base/power/opp/opp.h +++ b/drivers/base/power/opp/opp.h @@ -129,6 +129,8 @@ struct device_list_opp { * @clock_latency_ns_max: Max clock latency in nanoseconds. * @shared_opp: OPP is shared between multiple devices. * @suspend_opp: Pointer to OPP to be used during device suspend. + * @supported_hw: Array of version number to support. + * @supported_hw_count: Number of elements in supported_hw array. * @dentry: debugfs dentry pointer of the real device directory (not links). * @dentry_name: Name of the real dentry. * @@ -153,6 +155,9 @@ struct device_opp { bool shared_opp; struct dev_pm_opp *suspend_opp; + unsigned int *supported_hw; + unsigned int supported_hw_count; + #ifdef CONFIG_DEBUG_FS struct dentry *dentry; char dentry_name[NAME_MAX]; diff --git a/include/linux/pm_opp.h b/include/linux/pm_opp.h index 9a2e50337af9..3a85110242f0 100644 --- a/include/linux/pm_opp.h +++ b/include/linux/pm_opp.h @@ -55,6 +55,9 @@ int dev_pm_opp_enable(struct device *dev, unsigned long freq); int dev_pm_opp_disable(struct device *dev, unsigned long freq); struct srcu_notifier_head *dev_pm_opp_get_notifier(struct device *dev); +int dev_pm_opp_set_supported_hw(struct device *dev, const u32 *versions, + unsigned int count); +void dev_pm_opp_put_supported_hw(struct device *dev); #else static inline unsigned long dev_pm_opp_get_voltage(struct dev_pm_opp *opp) { @@ -129,6 +132,16 @@ static inline struct srcu_notifier_head *dev_pm_opp_get_notifier( { return ERR_PTR(-EINVAL); } + +static inline int dev_pm_opp_set_supported_hw(struct device *dev, + const u32 *versions, + unsigned int count) +{ + return -EINVAL; +} + +static inline void dev_pm_opp_put_supported_hw(struct device *dev) {} + #endif /* CONFIG_PM_OPP */ #if defined(CONFIG_PM_OPP) && defined(CONFIG_OF) -- cgit v1.2.3 From 01fb4d3c39d35b725441e8a9a26b3f3ad67793ed Mon Sep 17 00:00:00 2001 From: Viresh Kumar Date: Wed, 9 Dec 2015 08:01:47 +0530 Subject: PM / OPP: Parse 'opp--' bindings OPP bindings (for few properties) allow a platform to choose a value/range among a set of available options. The options are present as opp--, where the platform needs to supply the string. The OPP properties which allow such an option are: opp-microvolt and opp-microamp. Add support to the OPP-core to parse these bindings, by introducing dev_pm_opp_{set|put}_prop_name() APIs. Signed-off-by: Viresh Kumar Tested-by: Lee Jones Signed-off-by: Rafael J. Wysocki --- drivers/base/power/opp/core.c | 165 ++++++++++++++++++++++++++++++++++++++---- drivers/base/power/opp/opp.h | 2 + include/linux/pm_opp.h | 9 +++ 3 files changed, 161 insertions(+), 15 deletions(-) (limited to 'drivers/base/power') diff --git a/drivers/base/power/opp/core.c b/drivers/base/power/opp/core.c index 55cf1a99b532..5c01fec1ed14 100644 --- a/drivers/base/power/opp/core.c +++ b/drivers/base/power/opp/core.c @@ -562,6 +562,9 @@ static void _remove_device_opp(struct device_opp *dev_opp) if (dev_opp->supported_hw) return; + if (dev_opp->prop_name) + return; + list_dev = list_first_entry(&dev_opp->dev_list, struct device_list_opp, node); @@ -794,35 +797,48 @@ unlock: } /* TODO: Support multiple regulators */ -static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev) +static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev, + struct device_opp *dev_opp) { u32 microvolt[3] = {0}; u32 val; int count, ret; + struct property *prop = NULL; + char name[NAME_MAX]; + + /* Search for "opp-microvolt-" */ + if (dev_opp->prop_name) { + sprintf(name, "opp-microvolt-%s", dev_opp->prop_name); + prop = of_find_property(opp->np, name, NULL); + } + + if (!prop) { + /* Search for "opp-microvolt" */ + name[13] = '\0'; + prop = of_find_property(opp->np, name, NULL); - /* Missing property isn't a problem, but an invalid entry is */ - if (!of_find_property(opp->np, "opp-microvolt", NULL)) - return 0; + /* Missing property isn't a problem, but an invalid entry is */ + if (!prop) + return 0; + } - count = of_property_count_u32_elems(opp->np, "opp-microvolt"); + count = of_property_count_u32_elems(opp->np, name); if (count < 0) { - dev_err(dev, "%s: Invalid opp-microvolt property (%d)\n", - __func__, count); + dev_err(dev, "%s: Invalid %s property (%d)\n", + __func__, name, count); return count; } /* There can be one or three elements here */ if (count != 1 && count != 3) { - dev_err(dev, "%s: Invalid number of elements in opp-microvolt property (%d)\n", - __func__, count); + dev_err(dev, "%s: Invalid number of elements in %s property (%d)\n", + __func__, name, count); return -EINVAL; } - ret = of_property_read_u32_array(opp->np, "opp-microvolt", microvolt, - count); + ret = of_property_read_u32_array(opp->np, name, microvolt, count); if (ret) { - dev_err(dev, "%s: error parsing opp-microvolt: %d\n", __func__, - ret); + dev_err(dev, "%s: error parsing %s: %d\n", __func__, name, ret); return -EINVAL; } @@ -830,7 +846,20 @@ static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev) opp->u_volt_min = microvolt[1]; opp->u_volt_max = microvolt[2]; - if (!of_property_read_u32(opp->np, "opp-microamp", &val)) + /* Search for "opp-microamp-" */ + prop = NULL; + if (dev_opp->prop_name) { + sprintf(name, "opp-microamp-%s", dev_opp->prop_name); + prop = of_find_property(opp->np, name, NULL); + } + + if (!prop) { + /* Search for "opp-microamp" */ + name[12] = '\0'; + prop = of_find_property(opp->np, name, NULL); + } + + if (prop && !of_property_read_u32(opp->np, name, &val)) opp->u_amp = val; return 0; @@ -948,6 +977,112 @@ unlock: } EXPORT_SYMBOL_GPL(dev_pm_opp_put_supported_hw); +/** + * dev_pm_opp_set_prop_name() - Set prop-extn name + * @dev: Device for which the regulator has to be set. + * @name: name to postfix to properties. + * + * This is required only for the V2 bindings, and it enables a platform to + * specify the extn to be used for certain property names. The properties to + * which the extension will apply are opp-microvolt and opp-microamp. OPP core + * should postfix the property name with - while looking for them. + * + * Locking: The internal device_opp and opp structures are RCU protected. + * Hence this function internally uses RCU updater strategy with mutex locks + * to keep the integrity of the internal data structures. Callers should ensure + * that this function is *NOT* called under RCU protection or in contexts where + * mutex cannot be locked. + */ +int dev_pm_opp_set_prop_name(struct device *dev, const char *name) +{ + struct device_opp *dev_opp; + int ret = 0; + + /* Hold our list modification lock here */ + mutex_lock(&dev_opp_list_lock); + + dev_opp = _add_device_opp(dev); + if (!dev_opp) { + ret = -ENOMEM; + goto unlock; + } + + /* Make sure there are no concurrent readers while updating dev_opp */ + WARN_ON(!list_empty(&dev_opp->opp_list)); + + /* Do we already have a prop-name associated with dev_opp? */ + if (dev_opp->prop_name) { + dev_err(dev, "%s: Already have prop-name %s\n", __func__, + dev_opp->prop_name); + ret = -EBUSY; + goto err; + } + + dev_opp->prop_name = kstrdup(name, GFP_KERNEL); + if (!dev_opp->prop_name) { + ret = -ENOMEM; + goto err; + } + + mutex_unlock(&dev_opp_list_lock); + return 0; + +err: + _remove_device_opp(dev_opp); +unlock: + mutex_unlock(&dev_opp_list_lock); + + return ret; +} +EXPORT_SYMBOL_GPL(dev_pm_opp_set_prop_name); + +/** + * dev_pm_opp_put_prop_name() - Releases resources blocked for prop-name + * @dev: Device for which the regulator has to be set. + * + * This is required only for the V2 bindings, and is called for a matching + * dev_pm_opp_set_prop_name(). Until this is called, the device_opp structure + * will not be freed. + * + * Locking: The internal device_opp and opp structures are RCU protected. + * Hence this function internally uses RCU updater strategy with mutex locks + * to keep the integrity of the internal data structures. Callers should ensure + * that this function is *NOT* called under RCU protection or in contexts where + * mutex cannot be locked. + */ +void dev_pm_opp_put_prop_name(struct device *dev) +{ + struct device_opp *dev_opp; + + /* Hold our list modification lock here */ + mutex_lock(&dev_opp_list_lock); + + /* Check for existing list for 'dev' first */ + dev_opp = _find_device_opp(dev); + if (IS_ERR(dev_opp)) { + dev_err(dev, "Failed to find dev_opp: %ld\n", PTR_ERR(dev_opp)); + goto unlock; + } + + /* Make sure there are no concurrent readers while updating dev_opp */ + WARN_ON(!list_empty(&dev_opp->opp_list)); + + if (!dev_opp->prop_name) { + dev_err(dev, "%s: Doesn't have a prop-name\n", __func__); + goto unlock; + } + + kfree(dev_opp->prop_name); + dev_opp->prop_name = NULL; + + /* Try freeing device_opp if this was the last blocking resource */ + _remove_device_opp(dev_opp); + +unlock: + mutex_unlock(&dev_opp_list_lock); +} +EXPORT_SYMBOL_GPL(dev_pm_opp_put_prop_name); + static bool _opp_is_supported(struct device *dev, struct device_opp *dev_opp, struct device_node *np) { @@ -1042,7 +1177,7 @@ static int _opp_add_static_v2(struct device *dev, struct device_node *np) if (!of_property_read_u32(np, "clock-latency-ns", &val)) new_opp->clock_latency_ns = val; - ret = opp_parse_supplies(new_opp, dev); + ret = opp_parse_supplies(new_opp, dev, dev_opp); if (ret) goto free_opp; diff --git a/drivers/base/power/opp/opp.h b/drivers/base/power/opp/opp.h index 70f4564a6ab9..690638ef36ee 100644 --- a/drivers/base/power/opp/opp.h +++ b/drivers/base/power/opp/opp.h @@ -131,6 +131,7 @@ struct device_list_opp { * @suspend_opp: Pointer to OPP to be used during device suspend. * @supported_hw: Array of version number to support. * @supported_hw_count: Number of elements in supported_hw array. + * @prop_name: A name to postfix to many DT properties, while parsing them. * @dentry: debugfs dentry pointer of the real device directory (not links). * @dentry_name: Name of the real dentry. * @@ -157,6 +158,7 @@ struct device_opp { unsigned int *supported_hw; unsigned int supported_hw_count; + const char *prop_name; #ifdef CONFIG_DEBUG_FS struct dentry *dentry; diff --git a/include/linux/pm_opp.h b/include/linux/pm_opp.h index 3a85110242f0..95403d2ccaf5 100644 --- a/include/linux/pm_opp.h +++ b/include/linux/pm_opp.h @@ -58,6 +58,8 @@ struct srcu_notifier_head *dev_pm_opp_get_notifier(struct device *dev); int dev_pm_opp_set_supported_hw(struct device *dev, const u32 *versions, unsigned int count); void dev_pm_opp_put_supported_hw(struct device *dev); +int dev_pm_opp_set_prop_name(struct device *dev, const char *name); +void dev_pm_opp_put_prop_name(struct device *dev); #else static inline unsigned long dev_pm_opp_get_voltage(struct dev_pm_opp *opp) { @@ -142,6 +144,13 @@ static inline int dev_pm_opp_set_supported_hw(struct device *dev, static inline void dev_pm_opp_put_supported_hw(struct device *dev) {} +static inline int dev_pm_opp_set_prop_name(struct device *dev, const char *name) +{ + return -EINVAL; +} + +static inline void dev_pm_opp_put_prop_name(struct device *dev) {} + #endif /* CONFIG_PM_OPP */ #if defined(CONFIG_PM_OPP) && defined(CONFIG_OF) -- cgit v1.2.3 From a436b6a19f57656a6557439523923d89eb4a880d Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Thu, 17 Dec 2015 02:54:26 +0100 Subject: PM / runtime: Add new helper for conditional usage count incrementation Introduce a new runtime PM function, pm_runtime_get_if_in_use(), that will increment the device's runtime PM usage counter and return 1 if its status is RPM_ACTIVE and its usage counter is greater than 0 at the same time (0 will be returned otherwise). This is useful for things that should only be done if the device is active (from the runtime PM perspective) and used by somebody (as indicated by the usage counter) already and they are not worth bothering otherwise. Requested-by: Imre Deak Reviewed-by: Ulf Hansson Signed-off-by: Rafael J. Wysocki --- Documentation/power/runtime_pm.txt | 6 ++++++ drivers/base/power/runtime.c | 24 ++++++++++++++++++++++++ include/linux/pm_runtime.h | 5 +++++ 3 files changed, 35 insertions(+) (limited to 'drivers/base/power') diff --git a/Documentation/power/runtime_pm.txt b/Documentation/power/runtime_pm.txt index 0784bc3a2ab5..7328cf85236c 100644 --- a/Documentation/power/runtime_pm.txt +++ b/Documentation/power/runtime_pm.txt @@ -371,6 +371,12 @@ drivers/base/power/runtime.c and include/linux/pm_runtime.h: - increment the device's usage counter, run pm_runtime_resume(dev) and return its result + int pm_runtime_get_if_in_use(struct device *dev); + - return -EINVAL if 'power.disable_depth' is nonzero; otherwise, if the + runtime PM status is RPM_ACTIVE and the runtime PM usage counter is + nonzero, increment the counter and return 1; otherwise return 0 without + changing the counter + void pm_runtime_put_noidle(struct device *dev); - decrement the device's usage counter diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c index ab3fcd9f6c98..4c7055009bd6 100644 --- a/drivers/base/power/runtime.c +++ b/drivers/base/power/runtime.c @@ -965,6 +965,30 @@ int __pm_runtime_resume(struct device *dev, int rpmflags) } EXPORT_SYMBOL_GPL(__pm_runtime_resume); +/** + * pm_runtime_get_if_in_use - Conditionally bump up the device's usage counter. + * @dev: Device to handle. + * + * Return -EINVAL if runtime PM is disabled for the device. + * + * If that's not the case and if the device's runtime PM status is RPM_ACTIVE + * and the runtime PM usage counter is nonzero, increment the counter and + * return 1. Otherwise return 0 without changing the counter. + */ +int pm_runtime_get_if_in_use(struct device *dev) +{ + unsigned long flags; + int retval; + + spin_lock_irqsave(&dev->power.lock, flags); + retval = dev->power.disable_depth > 0 ? -EINVAL : + dev->power.runtime_status == RPM_ACTIVE + && atomic_inc_not_zero(&dev->power.usage_count); + spin_unlock_irqrestore(&dev->power.lock, flags); + return retval; +} +EXPORT_SYMBOL_GPL(pm_runtime_get_if_in_use); + /** * __pm_runtime_set_status - Set runtime PM status of a device. * @dev: Device to handle. diff --git a/include/linux/pm_runtime.h b/include/linux/pm_runtime.h index 3bdbb4189780..7af093d6a4dd 100644 --- a/include/linux/pm_runtime.h +++ b/include/linux/pm_runtime.h @@ -39,6 +39,7 @@ extern int pm_runtime_force_resume(struct device *dev); extern int __pm_runtime_idle(struct device *dev, int rpmflags); extern int __pm_runtime_suspend(struct device *dev, int rpmflags); extern int __pm_runtime_resume(struct device *dev, int rpmflags); +extern int pm_runtime_get_if_in_use(struct device *dev); extern int pm_schedule_suspend(struct device *dev, unsigned int delay); extern int __pm_runtime_set_status(struct device *dev, unsigned int status); extern int pm_runtime_barrier(struct device *dev); @@ -143,6 +144,10 @@ static inline int pm_schedule_suspend(struct device *dev, unsigned int delay) { return -ENOSYS; } +static inline int pm_runtime_get_if_in_use(struct device *dev) +{ + return -EINVAL; +} static inline int __pm_runtime_set_status(struct device *dev, unsigned int status) { return 0; } static inline int pm_runtime_barrier(struct device *dev) { return 0; } -- cgit v1.2.3 From fd8d8e63467c922be9ae4452cca2980d473477d9 Mon Sep 17 00:00:00 2001 From: Bartlomiej Zolnierkiewicz Date: Thu, 17 Dec 2015 19:04:38 +0100 Subject: PM / OPP: Fix parsing of opp-microvolt and opp-microamp properties Commit 01fb4d3c39d3 ("PM / OPP: Parse 'opp--' bindings") broke support for parsing standard opp-microvolt and opp-microamp properties. Fix it by setting 'name' string to proper value for !prop cases. Fixes: 01fb4d3c39d3 ("PM / OPP: Parse 'opp-- 'bindings") Signed-off-by: Bartlomiej Zolnierkiewicz Acked-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki --- drivers/base/power/opp/core.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'drivers/base/power') diff --git a/drivers/base/power/opp/core.c b/drivers/base/power/opp/core.c index 5c01fec1ed14..cd230c63aee6 100644 --- a/drivers/base/power/opp/core.c +++ b/drivers/base/power/opp/core.c @@ -814,7 +814,7 @@ static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev, if (!prop) { /* Search for "opp-microvolt" */ - name[13] = '\0'; + sprintf(name, "opp-microvolt"); prop = of_find_property(opp->np, name, NULL); /* Missing property isn't a problem, but an invalid entry is */ @@ -855,7 +855,7 @@ static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev, if (!prop) { /* Search for "opp-microamp" */ - name[12] = '\0'; + sprintf(name, "opp-microamp"); prop = of_find_property(opp->np, name, NULL); } -- cgit v1.2.3 From 4295733eee4e69eda432d95765b7762dc6013271 Mon Sep 17 00:00:00 2001 From: Manuel Pégourié-Gonnard Date: Tue, 29 Dec 2015 11:03:21 +0100 Subject: PM / core: fix typo in documentation MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The documentation for detach() said attach. Signed-off-by: Manuel Pégourié-Gonnard Acked-by: Pavel Machek Signed-off-by: Rafael J. Wysocki --- drivers/base/power/common.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/base/power') diff --git a/drivers/base/power/common.c b/drivers/base/power/common.c index f32b802b98f4..f48e33385b3e 100644 --- a/drivers/base/power/common.c +++ b/drivers/base/power/common.c @@ -112,7 +112,7 @@ EXPORT_SYMBOL_GPL(dev_pm_domain_attach); /** * dev_pm_domain_detach - Detach a device from its PM domain. - * @dev: Device to attach. + * @dev: Device to detach. * @power_off: Used to indicate whether we should power off the device. * * This functions will reverse the actions from dev_pm_domain_attach() and thus -- cgit v1.2.3 From d9de19b1cc013433ad293365b5b3902ec73dfd60 Mon Sep 17 00:00:00 2001 From: Pi-Cheng Chen Date: Mon, 28 Dec 2015 21:06:17 +0800 Subject: PM / OPP: Set cpu_dev->id in cpumask first Set cpu_dev->id in cpumask first when setting up cpumask for CPUs that share the same OPP table. This might be helpful when handling cpumask without the original CPU bitfield set. Signed-off-by: Pi-Cheng Chen Acked-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki --- drivers/base/power/opp/cpu.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'drivers/base/power') diff --git a/drivers/base/power/opp/cpu.c b/drivers/base/power/opp/cpu.c index 7b445e88a0d5..9f0c15570f64 100644 --- a/drivers/base/power/opp/cpu.c +++ b/drivers/base/power/opp/cpu.c @@ -214,7 +214,6 @@ EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_add_table); /* * Works only for OPP v2 bindings. * - * cpumask should be already set to mask of cpu_dev->id. * Returns -ENOENT if operating-points-v2 bindings aren't supported. */ int dev_pm_opp_of_get_sharing_cpus(struct device *cpu_dev, cpumask_var_t cpumask) @@ -230,6 +229,8 @@ int dev_pm_opp_of_get_sharing_cpus(struct device *cpu_dev, cpumask_var_t cpumask return -ENOENT; } + cpumask_set_cpu(cpu_dev->id, cpumask); + /* OPPs are shared ? */ if (!of_property_read_bool(np, "opp-shared")) goto put_cpu_node; -- cgit v1.2.3 From 5ff24d601092b222340b28466e263b1c4559407e Mon Sep 17 00:00:00 2001 From: Viresh Kumar Date: Tue, 5 Jan 2016 16:15:54 +0530 Subject: PM / OPP: Use snprintf() instead of sprintf() sprintf() can access memory outside of the range of the character array, and is risky in some situations. The driver specified prop_name string can be longer than NAME_MAX here (only an attacker will do that though) and so blindly copying it into the character array of size NAME_MAX isn't safe. Instead we must use snprintf() here. Reported-by: Geert Uytterhoeven Signed-off-by: Viresh Kumar Acked-by: Geert Uytterhoeven Acked-by: Stephen Boyd Signed-off-by: Rafael J. Wysocki --- drivers/base/power/opp/core.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'drivers/base/power') diff --git a/drivers/base/power/opp/core.c b/drivers/base/power/opp/core.c index cd230c63aee6..cf351d3dab1c 100644 --- a/drivers/base/power/opp/core.c +++ b/drivers/base/power/opp/core.c @@ -808,7 +808,8 @@ static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev, /* Search for "opp-microvolt-" */ if (dev_opp->prop_name) { - sprintf(name, "opp-microvolt-%s", dev_opp->prop_name); + snprintf(name, sizeof(name), "opp-microvolt-%s", + dev_opp->prop_name); prop = of_find_property(opp->np, name, NULL); } @@ -849,7 +850,8 @@ static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev, /* Search for "opp-microamp-" */ prop = NULL; if (dev_opp->prop_name) { - sprintf(name, "opp-microamp-%s", dev_opp->prop_name); + snprintf(name, sizeof(name), "opp-microamp-%s", + dev_opp->prop_name); prop = of_find_property(opp->np, name, NULL); } -- cgit v1.2.3 From d35818a9153e7f230fd65dc935e001a1b9bc08ff Mon Sep 17 00:00:00 2001 From: Andy Shevchenko Date: Thu, 7 Jan 2016 12:49:31 +0200 Subject: PM / clk: don't leave clocks enabled when driver not bound There is a new notification BUS_NOTIFY_DRIVER_NOT_BOUND that is issued when driver fails during binding. In such case pm_clk_notify(), when PM_CLK=n, leaves clocks enabled. Undo operations that have been done in BUS_NOTIFY_BIND_DRIVER case. Signed-off-by: Andy Shevchenko Signed-off-by: Rafael J. Wysocki --- drivers/base/power/clock_ops.c | 1 + 1 file changed, 1 insertion(+) (limited to 'drivers/base/power') diff --git a/drivers/base/power/clock_ops.c b/drivers/base/power/clock_ops.c index 60ee5591ee8f..c39b8617280f 100644 --- a/drivers/base/power/clock_ops.c +++ b/drivers/base/power/clock_ops.c @@ -473,6 +473,7 @@ static int pm_clk_notify(struct notifier_block *nb, enable_clock(dev, NULL); } break; + case BUS_NOTIFY_DRIVER_NOT_BOUND: case BUS_NOTIFY_UNBOUND_DRIVER: if (clknb->con_ids[0]) { for (con_id = clknb->con_ids; *con_id; con_id++) -- cgit v1.2.3